In recent years, various methods have been proposed in fingerprint and palmprint recognition. Examples of optical method for recognizing fingerprint and palmprint include total reflection method, light-path separation method, and scanning method. In a total reflection method, light from a light source such as ambient light enters into a pixel, and is totally reflected on the surface of a package substrate. When a finger or palm touches the display panel, the total reflection condition of the surface changes locally upon touch, leading to a disruption of the total reflection locally. The disruption of the total reflection results in a reduced reflection. Based on this principle, the ridge lines of a finger may be differentiated from the valley lines. Alternatively, fingerprint and palmprint may be recognized by detecting changes in capacitance when a finger touches the display panel.
In conventional fingerprint recognition display panels, the photosensor and other associated components are disposed in the subpixel regions of the pixels, decreasing aperture ratio of the display panel.